TWI509292B - Lens and lens module having lens - Google Patents

Description

Lens and lens module having the same

The invention relates to a lens and a lens module, in particular to a lens with an anti-reflection film and a lens module having the same.

In order to reduce the generation of glare, an anti-reflection film is generally deposited on the surface of the lens. The reflection spectrum curve of a previous anti-reflection film is shown in Fig. 6.

The surface of the optic portion of the lens is generally a curved surface, such as a spherical surface or an aspheric surface. When the anti-reflection film is deposited on a lens with a curved surface, the reflection spectrum curves of the central region and the edge region of the optical portion of the lens are often different. Generally, the reflection spectrum curve of the edge region is shifted to a short wave, as shown in FIG. In Fig. 7, the solid line represents the reflection spectrum curve of the central region, and the broken line represents the reflection spectrum curve of the edge region. As can be seen from Figure 7, the edge region has a reflectance greater than 5% for light having a wavelength greater than 450 nm. This will result in poor anti-reflection effect of the lens, which will cause more severe glare inside the lens, which will affect the imaging quality of the lens.

In view of this, it is necessary to provide a lens and lens module with better anti-reflection effect.

A lens comprising an optic and a non-optical portion surrounding the optic. The optic is for allowing light to penetrate for optical imaging, the optic having opposing first and second surfaces. The first surface has a curvature greater than zero and the first surface is deposited with an anti-reflective film. The antireflection film has a small reflectance in a wavelength range of 400 nm to 850 nm. At 2%. The optical portion has a reflectance of less than 2% in a wavelength range of 420 nm to 650 nm. The anti-reflection film includes first to eighth films sequentially deposited on the first surface, and the first to eighth films are respectively: a first film having a film thickness of 8.84 nm made of titanium dioxide, and cerium oxide a second film having a film thickness of 46.07 nm, a third film having a film thickness of 27.57 nm made of titanium dioxide, a fourth film having a film thickness of 20.39 nm made of cerium oxide, and a material of titanium dioxide. a fifth film having a film thickness of 75.34 nm, a sixth film having a film thickness of 13.68 nm using cerium oxide, a seventh film having a film thickness of 29.06 nm made of titanium oxide, and a film made of cerium oxide. An eighth film having a thickness of 100.33 nm.

A lens comprising an optic and a non-optical portion surrounding the optic. The optic is for allowing light to penetrate for optical imaging, the optic having opposing first and second surfaces. The first surface has a curvature greater than zero and the first surface is deposited with an anti-reflective film. The improvement is that the antireflection film has a reflectance of less than 2% in a wavelength range of 400 nm to 850 nm. The optical portion has a reflectance of less than 2% in a wavelength range of 420 nm to 650 nm. The anti-reflection film includes first to eighth films sequentially deposited on the first surface, and the first to eighth films are respectively: a first film having a film thickness of 13.80 nm made of titanium dioxide, and cerium oxide a second film having a film thickness of 43.70 nm, a third film having a film thickness of 37.65 nm made of titanium dioxide, a fourth film having a film thickness of 15.97 nm made of cerium oxide, and a material of titanium dioxide. a fifth film having a film thickness of 90.79 nm, a sixth film having a film thickness of 18.81 nm using cerium oxide, a seventh film having a film thickness of 30.13 nm made of titanium oxide, and a film made of cerium oxide. The eighth film having a thickness of 109.95 nm.

A lens module includes a lens barrel and a lens of any one of the above, the lens being housed in the lens barrel.

By adopting the anti-reflection film described above, the optical portion of the lens has a reflectance of less than 2% in a wavelength range of 420 nm to 650 nm, thereby reducing glare of the lens module having the lens, thereby improving the imaging quality of the lens module.

10‧‧‧ lenses

12‧‧‧Optical Department

14‧‧‧Non-optics

16‧‧‧Anti-reflective film

121‧‧‧ first surface

122‧‧‧ second surface

123‧‧‧Central area

124‧‧‧Edge area

141‧‧‧ third surface

142‧‧‧ fourth surface

20‧‧‧Lens module

22‧‧‧Mirror tube

222‧‧‧ accommodating space

1 is a schematic cross-sectional view of a lens according to a first embodiment of the present invention.

2 is a reflection spectrum curve of the anti-reflection film of FIG. 1.

3 is a reflection spectrum curve of the lens of FIG. 1.

4 is a cross-sectional view showing a lens module according to a second embodiment of the present invention.

Fig. 5 is a reflection spectrum curve of the antireflection film of the third embodiment.

Figure 6 is a reflection spectrum curve of a prior antireflection film.

Figure 7 is a reflection spectrum curve of a prior lens.

The invention will be further described in detail below with reference to the drawings and embodiments.

Referring to FIG. 1, a lens 10 according to a first embodiment of the present invention includes an optical portion 12, a non-optical portion 14 surrounding the optical portion 12, and an anti-reflection film 16 formed on the surface of the optical portion 12. The optic portion 12 is used to allow light to penetrate for optical imaging. The optical portion 12 includes an opposite first surface 121 and a second surface 122, and the non-optical portion 14 includes opposing third and second surfaces 141, 142, the first surface 121 is coupled to the third surface 141, and the third surface 141 is The four surfaces 142 are connected. In the present embodiment, the lens 10 is a convex lens. Both the first surface 121 and the second surface 122 are aspherical, and the curvature of the first surface 121 and the second surface 122 are both greater than zero. The third surface 141 and the fourth surface 142 are both planar. The first to fourth surfaces 121-122, 141-142 are each deposited with an anti-reflection film 16.

The anti-reflection film 16 is formed by alternately stacking a film of a high refractive index material and a film of a low refractive index material. In the present embodiment, the anti-reflection film 16 is formed by sequentially stacking eight layers of thin films, the high refractive index material is titanium dioxide, and the low refractive index material is cerium oxide. The specific structure of the anti-reflection film 16 is as shown in Table 1, in which the first film directly forms the first to fourth surfaces 121-122, 141-142.

The reflection spectrum curve of the anti-reflection film 16 is as shown in FIG. As can be seen from FIG. 2, the antireflection film 16 has a reflectance of less than 2% in the wavelength range of 400 nm to 850 nm. The reflection spectrum curves of the central region 123 and the edge region 124 of the optical portion 12 are as shown in FIG. 3, in which a solid line represents a reflection spectrum curve of the central region 123, and a broken line represents a reflection spectrum curve of the edge region 124. As can be seen from FIG. 3, the reflectance spectral curves of the central region 123 and the edge region 124 have a reflectance of less than 2% in the wavelength range of 420 nm to 650 nm. For one In general, light with a wavelength range of 420 nm to 650 nm is involved in imaging, and the light in the remaining bands is basically filtered by the filter. Therefore, the lens 10 has a good anti-reflection effect and can reduce the glare of the lens module.

It can be understood that the high and low refractive index materials and their refractive indices can be selected by referring to the following materials: magnesium fluoride (1.38), cesium fluoride (1.47), cryolite (1.35), cerium oxide (1.47), aluminum oxide (1.63), Cerium oxide (1.85), antimony pentoxide (2.2), antimony oxide (2.19), zinc sulfide (2.27), titanium dioxide (2.41), antimony (3.5), antimony (4.0), and lead telluride (5.0).

It can be understood that the anti-reflection film 16 may also be formed only on the first surface 121 or only on the first surface 121 and the third surface 141.

Referring to FIG. 4 , the lens module 20 of the second embodiment of the present invention includes a lens barrel 22 and a lens 10 . The lens barrel 22 has a substantially cylindrical shape, and has a housing space 222 therein, and the lens 10 is housed in the housing space 222 of the lens barrel 22. Since the lens module 20 employs the above-described lens 10, glare can be reduced.

For the lens 10 having a larger curvature of the first surface 121 and the second surface 122, a wider band anti-reflection film 16 may be employed such that the reflection spectrum of the central region 123 and the edge region 124 is reflected in the wavelength range of 420 nm to 650 nm. The rate is less than 2%. For example, the anti-reflection film 16 of the third embodiment of the present invention as shown in Table 2, wherein the first film is directly formed on the first to fourth surfaces 121-122, 141-142.

The reflection spectrum curve of the anti-reflection film 16 of Table 2 is shown in Fig. 5. As can be seen from FIG. 5, the antireflection film 16 has a reflectance of less than 2% in the wavelength range of 400 nm to 1000 nm.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

10‧‧‧ lenses

12‧‧‧Optical Department

14‧‧‧Non-optics

16‧‧‧Anti-reflective film

121‧‧‧ first surface

122‧‧‧ second surface

123‧‧‧Central area

124‧‧‧Edge area

141‧‧‧ third surface

142‧‧‧ fourth surface

Claims (8)

A lens comprising an optic for allowing light to penetrate for optical imaging, and a non-optical portion surrounding the optic, the optic having opposing first and second surfaces, the first surface The curvature is greater than zero, and the first surface is deposited with an anti-reflection film, wherein the anti-reflection film has a reflectance of less than 2% in a wavelength range of 400 nm to 850 nm, and the optical portion has a wavelength range of 420 nm to 650 nm. The reflectance is less than 2%, and the anti-reflection film comprises first to eighth films sequentially deposited on the first surface, and the first to eighth films are respectively: the first film having a thickness of 8.84 nm using titanium dioxide as a material a film, a second film having a film thickness of 46.07 nm using cerium oxide, a third film having a film thickness of 27.57 nm using titanium dioxide, and a fourth film having a film thickness of 20.39 nm using cerium oxide as a material. a fifth film having a film thickness of 75.34 nm made of titanium dioxide, a sixth film having a film thickness of 13.68 nm made of cerium oxide, a seventh film having a film thickness of 29.06 nm made of titanium dioxide, and Cerium oxide as material 100.33nm thickness of the eighth thin film. The lens of claim 1, wherein the antireflection film is formed by alternately stacking a film of a high refractive index material and a film of a low refractive index material. A lens comprising an optic for allowing light to penetrate for optical imaging, and a non-optical portion surrounding the optic, the optic having opposing first and second surfaces, the first surface The curvature is greater than zero, and the first surface is deposited with an anti-reflection film, wherein the anti-reflection film has a reflectance of less than 2% in a wavelength range of 400 nm to 850 nm, and the optical portion has a wavelength range of 420 nm to 650 nm. The reflectance is less than 2%, and the anti-reflection film comprises first to eighth films sequentially deposited on the first surface, and the first to eighth films are respectively: the first film having a thickness of 13.80 nm using titanium dioxide as a material a film, a second film having a film thickness of 43.70 nm using cerium oxide, and a third film having a film thickness of 37.65 nm using titanium dioxide as a material a film, a fourth film having a film thickness of 15.97 nm using cerium oxide, a fifth film having a film thickness of 90.79 nm made of titanium oxide, and a sixth film having a film thickness of 18.81 nm using cerium oxide as a material. A seventh film having a film thickness of 30.13 nm made of titanium dioxide and an eighth film having a film thickness of 109.95 nm made of cerium oxide. The lens of claim 1, wherein the first surface is aspherical. The lens of claim 1, wherein the second surface is further deposited with the anti-reflection film. The lens of claim 1, wherein the non-optical portion includes an opposite third surface and a fourth surface, the third surface being coupled to the first surface, the fourth surface being opposite the second surface The third surface is further deposited with the anti-reflection film. The lens of claim 6, wherein the second surface and the fourth surface are further deposited with the anti-reflection film. A lens module comprising a lens barrel and the lens of any one of claims 1 to 7, wherein the lens is housed in the lens barrel.